In water skiing, a person planes across the water on one or two skis, or even on barefeet, while pulled by a boat or other means. One manner of skiing involves the use of water ski booms. Typically they are round bars extending across the gunnel of motor boats, as shown in FIG. 1. Booms are contrasted with the older familiar manner of connecting a water skier with the tow boat by affixing a line and hand-grip harness to the rear of the boat. Booms are convenient for several applications. First, they position the skier in the more quiescent water aside the boat. Second, the skier can be abreast the boat and thus receive instruction from persons in the boat. Third, the boom itself can be gripped, as compared to having a trailing line and harness, to provide the neophyte skier, especially, with more stability. Griping the boom also makes it easier to plane on the water when starting from the still position, because the skier's body is initially more nearly upright.
Booms which have lines and hand-grip harness, like those used for towing behind a boat, tend to be useful for persons learning basics or practicing advanced tricks. Depending on the line length the skier's location can be abreast or astern of the boat. An example of such kinds of booms is shown in Naypaver U.S. Pat. No. 4,480,577. Booms which are directly held by the skier are especially useful for neophyte water skiers and learners who are somewhat physically disabled. U.S. Pat. No. 3,390,658 of Jelks shows such kind of boom mounted off a sled towed behind the boat. When the boom is mounted athwart the boat gunnel, the skier will be adjacent the boat.
The present invention pertains to the latter kind of booms; those which are directly grasped by the skier. The gripping location should desirably have a relatively non-slip surface, especially in view of the lubricating effect of the splashed water and the likely unpracticed grip of the skier. Yet, good solutions have not been found or offered to the users.
Typically, the booms are made of a corrosion resisting metal, such as anodized almumimum. But bar stock has a characteristic smooth mill finish and as such bars are difficult to hold onto. If the bar is lightly knurled, the grip is not sufficiently improved. If the surface is heavily knurled, the result may be and distress to the skier's hands.
Polymer coatings, such as coatings of epoxy or polyester resins, are often put on metal marine objects for purposes of appearance and protection. However, such coatings typically replicate the finish of the underlying substrate, and if anything, they will tend to make it smoother. Thus, they per se are not particularly helpful in providing better grip. Where the boom crosses the boat gunnel it may from time to time impact it. Thus a sleeve of plastic is commonly slipped on the shaft for softening any blow but it is susceptible to slippage and increases the shaft diameter. Of course, anything that aids a person's grip on a boom ought not increase the diameter beyond that natural for typical children and adults nor reduce the diameter and structural strength. Other requirements are that the boom be durable and of low weight.
Thus, there is a need for improvements in booms, to obtain better gripping, while meeting the various other performance requirements and, of course, doing so in an economic manner.